Distinguishing native from non-native Phragmites australis can be challenging. Here we provide guidance to assist you in making this distinction. The morphological characters presented here are in order of stronger characters to weaker characters. Characters most readily identifiable in the field are leaf sheath adherence to the stem and stem glossiness. These characters are best used after mid-summer and in winter. Ligule height can be a strong character, but is not as readily identifiable in the field, although note that the thickness of the band of color along the ligule can be used in the field. Stand density, stem height, leaf color, and inflorescences are variable characters that are not reliable on their own for identification. A solid ID depends on using as many as 6 different characters. Information is provided here on each of these characters to provide additional context for distinguishing native from non-native Phragmites.
Report populations of suspected non-native Phragmites in the EDDMapS app. Along with your report, submit several photos including photos of the whole stand and images that show details of the inflorescences, leaf sheaths, and stem color/texture.